littledcsrodshop

iTrader: (1)

I have a question that may sound a bit elementry but here we go : My question is if you were running twin tanks in a single engine boat what would be the best way to plumb the fuel lines to the pump & be assured that drain evenly ?
The pickups are in the top.... Could I just come off of each tank with even length lines & then use a good Y block to Y them into 1 line before geting to the Electric fuel pump ?

Like I said this may be a simple question but if I do this I want to make sure that they drain evenly & not have it pulling out of 1 tank more than the other for some reason.

sabercatt

you need one of two things: your tee fitting to your pump to be below your tanks or a crossover tube from tank to tank (at the lowest point of your tank). both essentially doing the same thing, the fuel will seek a natural level point between the two tanks.

littledcsrodshop

iTrader: (1)

I would do a crossover tube but my problem is that the tanks ofcourse are foamed in below the floor & sandwiched by the stringers so there is not really a good way to do that.

Have you ever done the T fitting thing with 2 tanks into 1 fuel pump ?

Please don't take this derogatory but even though I would most likely have the fuel pump mounted low anyways , would it make any differance with the fuel having to be pulled from the bottom of the tank all the way to the top through the pickup tube that is mounted on the top of the tank ?

Like I said It will be mounted low anyways but I just don't know if it would make any differance if it was mounted below the bottom or if it was mounted anywhere between the bottom of the tank & the top since it is pulling off the top.
Again not trying top be a smart ... , just trying to learn somthing.

Thanks for the reply , Scott

Turbojack

You will never get two tanks to draw together so they both run down at the same time.. When I bought my boat the take farther from the T was using less fuel then the one near the T. I then went and added Hose to the one that was close to the T so they both had the same lenght hose. Now it is a crap shoot which one will use more fuel. One will always use more fuel then the other. I now (when tanks are full) start out so both tanks are being pulled from. Then once 1 tank gets 1/4 tank lower then the other, I close off the valve to the lower tank.

I believe what was being said was a hose coming from the bottom of each tank so they will seek a common level. But the problem with coming of the bottom of a tank is have a fuel leak and you are going have the tank of fuel in your boat. If the boat does not blow up first.

flying J

The only other way would be a transfer pump. Then you could pull off the top of the tanks and manually level them

nwimbush

Scott,

I understand the reasoning to your question about fuel pump location - if the pump has the suction to pull fuel up the to the top of the tank, over the hump, and down to the pump location, why does the pump have to be mounted below the gas level?

Well, it doesn't if you set it up with a bypass regulator- the bypass allows the pump to flow fuel back to the tank via the return line.

The issue arises when you use a static regulator - i.e. one that simply stops fuel flow. Once this occurs, there is no flow and no suction on the pump side, so the fuel "slides" away unless the pump is mounted below the fuel level....

Hope this helps..

littledcsrodshop

iTrader: (1)

Thanks for all the replys so far.

Turbojack : I was afraid of them not draining even with a T before the pump , even with equal length lines. You would think that they would drain even but as we know theory & reality don't always work out the same. Yeah I understand the Idea of 2 lines coming off the bottom to equalize the tanks but I just can't do that beacause of the fact that they are already foamed between the stringers & under the floor.

FlyingJ : I have thought alittle bit about how I could use another pump to help the situation. But if you don't care Please elaborate on exactly what you are saying.

nwimbush : If I go with a single I will definatly be using a bypass regulator ( probably the areomotive with the 1:1 rising with boost , not sure of the model # offhand but I think it is the A1000) because this will be on a supercharged application. It would be a blowthrough carbed centrifical Vortech.

all of this helps & again I appritiate all of your input & all I can say is keep it comming !!